This project aims at developing the Orion microscope system, a highly innovative combined software/hardware product, which will facilitate automated investigations of dynamics of migration of neuronal precursors and neurite outgrowth in vitro using time-lapse video-microscopy (TLVM). To achieve this goal, the Orion microscope system will combine novel software with two innovative microscope hardware devices that were recently developed and patented by MBF: (i) movable Extended Microscope Objective devices, and (ii) a dual- objective microscope setup. The Orion microscope system will allow investigators, for the first time, to inspect a tissue culture with two microscope objectives simultaneously (using fluorescence illumination), with the possibility of moving the objectives in XYZ directions independent of each other. This system will help uncover new discoveries about neuronal precursors and neurite outgrowth. The development of the mammalian brain is dependent on extensive migration of neuronal precursors. There is need for a better understanding of the regulation of (and correction of disturbed) migration of neuronal precursors in the developing brain, in order to develop novel approaches for preventing and treating various neurological and neuropsychiatric disorders such as childhood-onset epilepsy, autism, schizophrenia, attention deficit hyperactivity disorder, lissencephaly, and the neurologic and neurobehavioral sequelae seen in children with HIV-1 infection. Furthermore, better insights into the dynamics of neurite outgrowth (and particularly the correction of impaired neurite outgrowth) have become an important aspect in the development of novel therapeutic strategies to combat neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and NeuroAIDS. To study the dynamics of neuronal precursor migration and neurite outgrowth, investigators usually perform TLVM on dissociated neuron cultures or organotypic slice cultures of the brain in vitro, inspecting single fields-of-view. Several software and combined software/hardware products exist to assist investigators in such studies. However, none of these products comprise the following functionality that is considered critical in advanced, automated analyses of the dynamics of migration of neuronal precursors and neurite outgrowth: (i) identifying and follow up migrating neuronal precursors and growing neurites across many microscopic fields-of-view within large tissue cultures at low magnification and, simultaneously, (ii) determining the different modes of migration of the identified migrating neuronal precursors or subtle changes in growing neurites at high magnification. This will open new horizons in understanding the dynamic behaviors of neurons during development, re-organization, and degeneration of the brain, with high relevance for both neuroscience research and the development of novel therapeutic strategies to prevent or combat the aforementioned disorders. Accordingly, the development of the Orion microscope system represents clear progress beyond the state-of-the-art, with great benefits for the neuroscience research community and society in general.